Texas executed Jonathan Green for the 2000 murder of a 12-year-old girl Wednesday night after the U.S. Supreme Court rejected his last minute appeal.

James Rytting, Green’s lawyer, maintained that his client was mentally incompenent and suffered from hallucinations about the “ongoing spiritual warfare between two sets of voices representing good and evil,” according to Michael Graczyk of the Associated Press.

A federal judge in Houston blocked Green’s execution Monday, ruling that Green’s rights to due process were violated during his competency hearing, according to KUT News.

But the U.S. Court of Appeals for the Fifth Circuit overturned that decision the following day, saying Green testified at his hearing, was provided counsel, was able to call his own expert witness, and submitted more than 200 pages of medical records, Chad Bray reported at the Wall Street Journal .

Green’s mental health was a central issue in the fight to prevent his execution. Green’s lawyers appealed ( PDF) in 2009 to have his execution stayed, arguing that Green’s due process rights were violated and that he was “incompetent to be executed because he has shown signs of severe psychosis.” His claims of incompetency were ultimately dismissed on each occasion, clearing the way for his execution October 10.

Green, 44, was sentenced to die in July 2002 for the abduction, sexual assault, and strangling death of 12-year-old Christina Neal, his neighbor. Christina had been missing for a month when investigators found her body propped up behind a chair in Green’s home, according to Graczyk and the Texas Department of Corrections. Investigators received a warrant after questioning Green about a large burn pile in his backyard, in which an FBI agent detected the scent of human remains.

Green’s final appeal was rejected less than two hours before his death warrant was set to expire, CBS News reported. He was pronounced dead at 10:45 p.m. Christina’s parents witnessed Green’s execution but declined comment to the media.

Jason Clark, a spokesman for the Texas Department of Criminal Justice, confirmed Green’s final words to the TM Daily Post : “I’m an innocent man. I did not kill anyone. Y’all are killing an innocent man,” Green said. “My left arm is killing me, it hurts bad.”

ThinkProgressnoted that three more Texans are scheduled for execution this month.